A Turkish hacker known as “Chao” and arrested as part of the FBI operation against underground forum DarkMarket produced his own training videos, researchers revealed this week at the RSA Europe conference in London.

RSA Consumer Solutions Head of New Technologies Uri Rivner said the hacker was behind the manufacture of hundreds of ATM skimming devices made from readily available parts, including switches from IKEA, and sold online.

But it the video that set Chao apart and which surprised the authorities when they saw it.

Surprisingly well made and even funny, it is full of tips for criminals on the best way to use a skimming device. Among the tips spoken in broken English on the video are:

Don’t install a skimmer in the morning, because people are more vigilant; don’t install skimmers in towns with fewer than 15,000 people, because people in those towns would notice changes to their local ATMs; avoid areas with small shops open 24 hours a day and don’t set up in areas where a lot of illegal immigrants live.